Researchers say this study is not about obesity, but "poor quality" diets damaging hearts and causing cancer.

So which diets have got it in for me?

The Global Burden of Disease Study is the most authoritative assessment of how people are dying in every country in the world.

The latest analysis used estimates of countries' eating habits to pin down how often diet was shortening lives.

The dangerous diets were those containing:

Too much salt - three million deaths

Too few whole grains - three million deaths

Too little fruit - two million deaths

Low levels of nuts, seeds, vegetables, omega-3 from seafood and fibre were the other major killers.

"We find that diet is one of the dominant drivers of health around the world, it's really quite profound," Prof Christopher Murray, the director of the Institute for Health Metrics and Evaluation at the University of Washington told the BBC.

Prof Nita Forouhi, from the University of Cambridge, said: "The perception is they are little packs of energy that will make you fat, whereas they are packed full of good fats.

"And most people don't see them as mainstream food; and the other issue is cost."

Image copyrightGetty ImagesImage caption
Nuts - they are not just for squirrels.

I thought meat and sugar were the bad guys?

The huge fat versus sugar debate and the link between red and processed meats with cancer have attracted huge headlines in recent years.

"These can be harmful as we show, but they are much smaller issues than low whole grains, fruit, nuts, seeds and vegetable intake," said Prof Murray.

Although, the study did show too many fizzy drinks were being drunk in every corner of the world.

The researchers say it is time for health campaigns to switch from talking about nutrients like fat and sugar and instead promote healthy foods.

But is a tasty unhealthy diet worth it?

Bad diets are knocking a couple of years off life expectancies around the world, according to the researchers.

But Prof Murray warns this is just the average and says the real question we should be asking is: "Am I going to die in my 50s from a heart attack? Or am I going to have some of the diet-related cancers in my 40s?"

Are any countries doing well?

Mediterranean countries, particularly France, Spain and Israel, have some of the lowest numbers of diet-related deaths in the world.

Countries in South East, Southern and Central Asia are at the opposite end of the spectrum.

Israel has the lowest diet-related deaths - 89 per 100,000 people a year

Uzbekistan has the highest diet-related deaths - 892 per 100,000 people a year

Japan and China have curiously contrasting fortunes that reflect their changing relationship with salt.

China consumes enormous amounts of salt with soy and other salty sauces being a key part of the country's cuisine.

But the rising popularity of processed foods is introducing yet more salt to their diet. It has the highest death rate because of salt of any country.

Prof Murray said: "Japan is very interesting because if you go back 30 to 40 years, they like China today had enormous salt intake.

"Salt is still their number one problem, but it has come down dramatically,

"And they have a diet that is higher in many of the things we think are protective for heart disease such as vegetables and fruit."

Image copyrightGetty ImagesImage caption
Soy sauce is high in salt

What about the UK?

The UK is behind countries like France, Denmark and Belgium.

The biggest problems are a lack of whole grains, fruit, vegetables and nuts and seeds.

The study estimates 14% of UK deaths are related to diet, with 127 diet-related deaths per 100,000 people a year.

Any advice?

"The really big story for people to act on is increase your whole grains, fruit, nuts, seeds and vegetable intake and reduce salt if you can."

But money is an issue.

It is estimated that having your five fruit and veg a day would take up 52% of household income in poorer countries.

But Prof Forouhi warns: "The public can make healthier choices if informed and have the resources, but if what is on the shelves as buy-one-get-one-free is always unhealthy, then that message will fall down.

"Cheaper options that are healthy are badly needed."

Both agreed there needed to be a shift from focusing on nutrients (fat/sugar/salt) and on to which actual foods people should eat.